The research in this proposal focuses on the development of visual form perception during early infancy. The proposal consists of two different yet related lines of research. The first involves the study of human infant form perception and its development. The preferential looking literature has been considered and the conclusion drawn that it does not provide a reasonable general characterization of the state of infant form perception. An altenative theoretical and experimental approach is proposed which involves use of the contrast sensitivity function. Several experiments are proposed to develop this line of research. The effects of stimulus pattern and temporal variations will be assessed quantitatively. The two visual systems theory as applied to early perception will be tested. The influence of acuity and contrast sensitivity on the perception of faces will be assessed. Different behavioral methodologies used in infant form perception will be compared. The second line of research involves the development of some sensorimotor abilities required for acute form perception. It is argued that the development of accommodation and refraction is intimately involved in the growth of form perception capabilities. Several experiments are proposed including: investigation of the mechanisms which underlie early changes in accommodation and refraction; further development of techniques for infant assessment; investigation of the role of early experience measurement errors in infant assessments. It is argued that the development of refraction and accommodation provides an excellent model for studying principles of general sensorimotor development.